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1

"Czarne złoto" - melaniny w życiu człowieka

100%

Łopusiewicz Ł., Lisiecki S.

Kosmos

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2016

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vol. 65

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issue 4

621-629

PL

Melaniny to ogólna nazwa grupy wielkocząsteczkowych barwników odpowiedzialnych za ciemną pigmentację organizmów. Powstają w wyniku oksydacyjnej polimeryzacji związków fenolowych i indolowych. Są to jedne z najbardziej powszechnych, heterogenicznych i odpornych na działanie różnych czynników pigmentów obecnych w przyrodzie. U człowieka powstają w melanosomach będących specyficznymi organellami melanocytów, komórek wyspecjalizowanych w przeprowadzaniu złożonego procesu melanogenezy. Ich rola w życiu człowieka jest wieloaspektowa. Chronią przed szkodliwym skutkiem nadmiernej ekspozycji na promieniowanie UV i powstającymi pod jego wpływem reaktywnymi formami tlenu. Są odpowiedzialne za pigmentację skóry, włosów, tęczówki. Biorą udział w prawidłowym przebiegu procesów widzenia i słyszenia oraz ochronie mózgu przed procesami neurodegeneracyjnymi. Są jednym z czynników wirulencji mikroorganizmów patogennych dla człowieka. Są obecne w niektórych produktach spożywczych, pozytywnie wpływając na ich działanie prozdrowotne. Znalazły również zastosowanie w nowoczesnej medycynie i technologii.

EN

Melanin is a general name of macromolecular dyes responsible for the dark pigmentation of organisms. They are products of oxidative polymerization of phenolic and indolic compounds, the most common, heterogenous and resistant to various factors pigments found in the nature. In man they are synthetized in melanosomes that are specific organelles of melanocytes, cells specialized in carrying out the complex process of melanogenesis. The role of melanin in human life is multiplex. Melanins protect against the harmful effects of excessive exposure to UV radiation and reactive oxygen species. They are responsible for skin, hair and iris pigmentation. They take part in the normal processes of vision and hearing and protect the brain against neurodegenerative processes. Melanins are one of the virulence factors of some pathogenic microorganisms. They are present in certain food products, thus improving their health-promoting effect. Melanins are also used in modern medicine and technology.

2

Biosynthesis of antibacterial silver nano-particles from Aspergillus terreus

100%

Singh P. S., Vidyasagar G. M.

World News of Natural Sciences

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2018

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vol. 16

109-116

EN

This paper deals with the bio-synthesis of silver nano-particles using a soil fungi. In this work, FTIR examinations indicated that the encountered soil particles actually contained Silver particles, while XRD analysis confirmed the silver was in the nano-crystalline phase. Moreover, the hurried decline of silver (Ag+) ions monitored using UV-visible spectrophotometer, demonstrated that these silver nano-particles formed within 19 minutes. In addition, transmission electron microscopy (TEM) revealed that the synthesized silver nano-particles come in a size ranging between 16-57 nm and have a variety of shapes, including round, rod and uneven. The present study thus concludes that silver nano-particles were actually produced and that these have admirable antibacterial activity. The current study also indicates that increasing concentration increases the rate of reduction and decreases the particle size.

3

Synthesis, spectral correlation analysis and evaluation of biological activities of some substituted hydrazones

88%

Vijayakumar R., Senbagam R., Rajarajan M., Balaji S., Manikandan V., Vanangamudi G., Thirunarayanan G.

Annales Universitatis Mariae Curie-Skłodowska, sectio AA – Chemia

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2015

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vol. 70

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issue 2

EN

Some novel substituted hydrazone derivatives of amino guanidine have been synthesized with different substituted benzaldehydes by condensation method. The synthesized hydrazones were characterized by their physical constants, UV, IR and NMR spectra. The spectral data have been correlated with Hammett substituent constants and Swain–Lupton parameters. From the result of statistical analysis, the effects of substituents on the spectral data have been predicted. The antimicrobial activities of these synthesized hydrazone compounds have been screened by Bauer-Kirby method using human pathogenic bacteria and fungal species. The antimicrobial activities of all synthesized hydrazone compounds have shown significant activity.

4

Synthesis, assessment of substituent effect and antimicrobial activities of some substituted (E)-Nbenzylidene- 5-bromopyridin-2-amines

88%

Senbagam R., Vanangamudi G., Thirunarayanan G.

Annales Universitatis Mariae Curie-Skłodowska, sectio AA – Chemia

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2015

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vol. 70

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issue 2

EN

A series of substituted (E)-N-benzylidene-5-bromopyridin-2-amine compounds have been synthesized from 5-bromo-2-aminopyridine with different substituted benzaldehydes. The structure of the adducts was confirmed by their physical constants, UV, IR and NMR spectral data. The observed UV absorption maximum λmaxC=N(nm), IR frequencies νC=N(cm-1), The 1H and 13C NMR δ(ppm) chemical shifts values have been correlated with Hammett substituent constants and F and R parameters using single and multi-linear regression analysis. From the results of statistical analysis, the effect of substituents on the spectral data has been studied. The antimicrobial activities of all synthesized imines have been studied using Bauer-Kirby method.

5

TiO2-assisted photodegradation of pharmaceuticals - a review

88%

Tong A., Braund R., Warren D., Peake B.

Open Chemistry

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2012

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vol. 10

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issue 4

989-1027

EN

Pharmaceutical compounds have been detected in the environment and potentially arise from the discharge of excreted and improperly disposed medication from sewage treatment facilities. In order to minimize environmental exposure of pharmaceutical residues, a potential technique to remove pharmaceuticals from water is the use of an advanced oxidation process (AOP) involving titanium dioxide (TiO2) photocatalysis. To evaluate the extent UV/TiO2 processes have been studied for pharmaceutical degradation, a literature search using the keywords ‘titanium dioxide’, ‘photocatalysis’, ‘advanced oxidation processes’, ‘pharmaceuticals’ and ‘degradation’ were used in the ISI Web of Knowledge TM, Scopus TM and ScienceDirect TM databases up to and including articles published on 23 November 2011. The degradation rates of pharmaceuticals under UV/TiO2 treatment were dependent on type and amount of TiO2 loading, pharmaceutical concentration, the presence of electron acceptors and pH. Complete mineralization under particular experimental conditions were reported for some pharmaceuticals; however, some experiments reported evolution of toxic intermediates during the photocatalytic process. It is concluded that the UV/TiO2 system is potentially a feasible wastewater treatment process, but careful consideration of the treatment time, the loading and the type of TiO2 (doped vs. undoped) used for a particular pharmaceutical is necessary for a successful application (198 words). [...]

6

UV Radiation Detection Using Optical Sensor Based on Eu3+ Doped PMMA

88%

Miluski P., Kochanowicz M., Żmojda J., Dorosz D.

Metrology and Measurement Systems

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2016

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vol. 23

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issue 4

7

Chemical characterization by TLC, UV, IR, HPLC-MS/MS and NMR of gossypetin-3’-O-glucoside from Talipariti elatum (Sw.) Malvaceae

75%

González J., Cuéllar A., Gaysinski M., Massi L., Monan M., Nossin E., François-Haugrin F.

World News of Natural Sciences

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2019

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vol. 24

100-116

EN

Talipariti elatum (Sw.) Malvaceae, also known as Blue Mahoe or Mountain Mahoe, commonly named as Majagua azul or Majagua, with red or crimson flowers, is a medicinal tree traditionally used against cough, asthma, catarrh, and expectorant. Its flowers contain a lot different chemical compounds, mainly flavonoids. From red petals of the flowers a flavonol glucoside was isolated and characterized by TLC, UV, IR, HPLC-MS/MS and NMR spectroscopy. Structure analyses of that chemical component revealed that It have the identical glucoside moiety attached to a flavonol skeleton like gossypitrin (gossypetin-7-O--glucoside) but in different position for which the structure of gossypetin-3’-O-glucoside was deduced from HSQC, HMBC, COSY and NOESY correlations.

8

DNA damage and alterations of gene expression in chronic-degenerative diseases.

63%

Izzotti A.

Acta Biochimica Polonica

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2003

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vol. 50

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issue 1

145-154

EN

Chronic-degenerative diseases (CDD) recognise a variety of exogenous and endogenous risk factors interacting with the organism for many years before disease onset. We applied genomic and postgenomic molecular analyses in experimental models characterised by different contribution of exogenous and endogenous CDD risk factors. Exposure of mice to halogen light for 28 days resulted in induction of cyclobutane dimers and oxidative DNA damage in the skin. Evaluation of postgenomic alterations by cDNA arrays revealed upregulation of DNA repair pathways, increased cell division rate and protooncogenes transcription, resulting in skin tumors, 1 year later. Exposure of p53-/+ mutant mice to cigarette smoke (CS) for 28 days induced DNA adducts formation in the lung. Postgenomic alterations included decreased apoptosis and increased cell division, as compared to CS-exposed wild type mice. These phenomena resulted in lung tumors, 9 months later. Transplacental exposure of mouse foetuses to cigarette smoke induced DNA adduct formation in the liver. cDNA arrays analyses demonstrated decreased cell division, apoptosis increase, and tissue hypoxia. These phenomena resulted in growth retardation of the whole organism. Molecular alterations were investigated in human trabecular meshwork, the non-replicating ocular epithelia involved in the pathogenesis of chronic degenerative glaucoma. Results indicate increased oxidative DNA damage in glaucoma patients as compared to unaffected controls. These four experimental studies suggest that DNA damage may result in different CDD (cancer, growth retardation, glaucoma) depending on the replication rate of the target cell population.

9

Interaction of fibrinogen with nanosilica

63%

Rugal A., Gun’ko V., Barvinchenko V., Turov V., Semeshkina T., Zarko V.

Open Chemistry

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2007

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vol. 5

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issue 1

32-54

EN

Interaction of human plasma fibrinogen (HPF) with fumed nanosilica A-300 in a phosphate buffer solution (PBS) was studied using 1H NMR spectroscopy with layer-by-layer freezing-out of bulk and interfacial water in the temperature range of 210–273 K, TSDC (90 T FTIR, and UV spectroscopy methods. An increase in concentration of HPF in the PBS leads to a decrease in amounts of structured water (frozen at T FTIR and UV spectra show that the HPF adsorption on silica leads to structural changes of the protein molecules. These changes and formation of hybrid HPF/A-300 aggregates can increase the rate of clotting that is of importance on nanosilica application as a component of tourniquet preparations. [...]

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"Czarne złoto" - melaniny w życiu człowieka

Biosynthesis of antibacterial silver nano-particles from Aspergillus terreus

Synthesis, spectral correlation analysis and evaluation of biological activities of some substituted hydrazones

Synthesis, assessment of substituent effect and antimicrobial activities of some substituted (E)-Nbenzylidene- 5-bromopyridin-2-amines

TiO2-assisted photodegradation of pharmaceuticals - a review

UV Radiation Detection Using Optical Sensor Based on Eu3+ Doped PMMA

Chemical characterization by TLC, UV, IR, HPLC-MS/MS and NMR of gossypetin-3’-O-glucoside from Talipariti elatum (Sw.) Malvaceae

DNA damage and alterations of gene expression in chronic-degenerative diseases.

Interaction of fibrinogen with nanosilica